*Minor differences ignored. Grouped by changes, with first version listed as example.
Where is Sarah? Hitherto God permitted Abraham to discharge an obvious duty. But, having given him the opportunity of exercising charity, God now begins to manifest himself in his angels. The reason why Moses introduces, at one time, three speakers, while, at another, he ascribes speech to one only, is, that the three together represent the person of one God. We must also remember what I have lately adduced, that the principal place is given to one; because Christ, who is the living image of the Father, often appeared to the fathers under the form of an angel, while, at the same time, he yet had angels, of whom he was the Head, for his attendants. And as to their making inquiry respecting Sarah; we may hence infer, that a son is again here promised to Abraham, because she had not been present at the former oracle.
And they said unto him, where is Sarah thy wife?.... One of them put the question; and so the Septuagint version renders it, "and he said unto him", the principal of them, whom Abraham at first addressed and called him "my Lord", and was no other than the Son of God in an human form; and various things in the context show him to be a divine Person, particularly his promise of return next year, and Sarah should have a son: and the question here put by him was not out of ignorance, for he who knew the name of Abraham's wife, knew where she was; but this was asked in order to lead on to say something more concerning her, and that, hearing her name, she might draw nearer and listen to what was said of her:
and he said, behold, in the tent; for in those times they dwelt in tents, and this was either the tent common to the family, or rather was Sarah's own tent, Genesis 24:67; Sarah was where she should be, in her own apartment, attending to the business of her family, and answered to the description the apostle gives of a good housewife, a keeper at home, Titus 2:5;
Where is Sarah thy wife? was asked. Note the answer, In the tent. Just at hand, in her proper place, occupied in her household concerns. There is nothing got by gadding. Those are most likely to receive comfort from God and his promises, who are in their proper place, and in the way of their duty, Luke 2:8. We are slow of heart to believe, and need line upon line to the same purport. The blessings others have from common providence, believers have from the Divine promise, which makes them very sweet, and very sure. The spiritual seed of Abraham owe their life, and joy, and hope, and all, to the promise. Sarah thinks this too good news to be true; she laughed, and therefore cannot as yet find in her heart to believe it. Sarah laughed. We might not have thought there was a difference between Sarah's laughter and Abraham's, Luke 17:17; but He who searches the heart, saw that the one sprung from unbelief, and the other from faith. She denied that she had laughed. One sin commonly brings in another, and it is not likely we shall strictly keep to truth, when we question the Divine truth. But whom the Lord loves he will rebuke, convict, silence, and bring to repentance, and if they sin before him.
During the meal, at which Abraham stood, and waited upon them as the host, they asked for Sarah, for whom the visit was chiefly intended. On being told that she was in the tent, where she could hear, therefore, all that passed under the tree in front of the tent, the one whom Abraham addressed as Adonai (my Lord), and who is called Jehovah in Genesis 18:13, said, "I will return to thee (חיּה כּעת) at this time, when it lives again" (חיּה, reviviscens, without the article, Ges. 111, 2b), i.e., at this time next year; "and, behold, Sarah, thy wife, will (then) have a son." Sarah heard this at the door of the tent; "and it was behind Him" (Jehovah), so that she could not be seen by Him as she stood at the door. But as the fulfilment of this promise seemed impossible to her, on account of Abraham's extreme age, and the fact that her own womb had lost the power of conception, she laughed within herself, thinking that she was not observed. But that she might know that the promise was made by the omniscient and omnipotent God, He reproved her for laughing, saying, "Is anything too wonderful (i.e., impossible) for Jehovah? at the time appointed I will return unto thee," etc.; and when her perplexity led her to deny it, He convicted her of falsehood. Abraham also had laughed at this promise (Genesis 17:17), and without receiving any reproof. For his laughing was the joyous outburst of astonishment; Sarah's, on the contrary, the result of doubt and unbelief, which had to be broken down by reproof, and, as the result showed, really was broken down, inasmuch as she conceived and bore a son, whom she could only have conceived in faith (Hebrews 11:11).
Where is Sarah thy wife? - By naming her, they gave intimation to Abraham, that tho' they seemed strangers, yet they well knew him and his family: by enquiring after her, they shewed a kind concern for the family of one, whom they found respectful to them. And by speaking of her, she over - hearing it, they drew her to listen to what was farther to be said.
*More commentary available at chapter level.